The work () done by the friction force between the ramp and the skateboarder is given by
.
The workdone by the friction force () can be calculated using the formula for work, which is the product of the force applied (
) and the displacement (d) over which the force is applied:
In this scenario, the frictionforce works against the skateboarder's momentum down the ramp, therefore it does no good.
Given:
Mass of skateboarder () = 54 kg
Height of the ramp () = 3.3 m
Final velocity () = 6.2 m/s
Coefficient of kineticfriction () between skateboarder and ramp
Acceleration due to gravity (g) =
The normal force () is equal to the weight of the skateboarder:
The displacement (d) is the vertical distance () that the skateboarder descends down the ramp.
Now we can write the expression for the work done by the friction force ():
Substitute the expression for the normal force:
Thus, this expression represents the work done by the friction force between the ramp and the skateboarder in terms of the given variables.
For more details regarding friction force visit:
#SPJ12
Your question seems incomplete, the probable complete question is:
A skateboarder with mass ms = 54 kg is standing at the top of a ramp which is hy = 3.3 m above the ground. The skateboarder then jumps on his skateboard and descends down the ramp. His speed at the bottom of the ramp is vf = 6.2 m/s.
Write an expression for the work, Wf, done by the friction force between the ramp and the skateboarder in terms of the variables given in the problem statement.
The momentum of the box with respect to the floor can be found by multiplying its mass by its velocity. When the box is put down on the frictionless skating surface, its velocity becomes zero and its momentum with respect to the floor is also zero.
To find the momentum of the box, we can use the formula:
Momentum = mass x velocity
a. The momentum of the box with respect to the floor is: 5 kg x 5 m/s = 25 kg·m/s
b. When the box is put down on the frictionless skating surface, its velocity becomes zero. So, the momentum of the box with respect to the floor is also zero.
#SPJ11
C)What would the swimmer's drop time be if the bridge were twice as high?
Answer: part a: 19.62m
part b: 19.62 m/s
part a: 2.83 secs
Explanation:If the air resistance is ignored then the swimmer experience free fall under gravity hence
u=0
a=9.81 m/s2
t=2 secs
s=h
Part b
Part c
now we have h=2*19.62=39.24
Answer:
4.93 m
Explanation:
According to the question, the computation of the height is shown below:
But before that first we need to find out the speed which is shown below:
As we know that
= 9.92 m/s
Now
98.4064 = 19.96 × height
So, the height is 4.93 m
We simply applied the above formulas so that the height i.e H could arrive
The height of the water slide is 5.04 meters.
The problem described in this question involves a water slide, where swimmers start from rest at the top and leave the slide traveling horizontally. To determine the height of the slide, we can use the equations of motion in the horizontal direction. The horizontal displacement (x) is given as 5.00 m and the time (t) is given as 0.504 s. Assuming no friction or air resistance, we can use the equation x = v*t, where v is the horizontal velocity. Rearranging the equation, we can solve for v, which is equal to x/t. Substituting the given values, we have v = 5.00 m / 0.504 s = 9.92 m/s. The horizontal velocity (v) is constant throughout the motion, so we can use the equation v = sqrt(2*g*H), where g is the acceleration due to gravity (9.8 m/s^2) and H is the height of the slide. Rearranging the equation, we can solve for H, which is equal to v^2 / (2*g). Substituting the known values, we have H = (9.92 m/s)^2 / (2*9.8 m/s^2) = 5.04 m.
Answer:
Acceleration,
Explanation:
Given that,
Initial speed of a car, u = 45 km/h = 12.5 m/s
Final speed, v = 0 (as they comes to rest)
Distance, d = 18 m
We need to find the acceleration of the breaking car. Using third equation of motion as follows :
So, the acceleration of the braking car is .
acceleration.
Answer:
(a) The average velocity is 16 m/s
(b) The acceleration is 0.4 m/s^2
(c) The final velocity is 24 m/s
Explanation:
Constant Acceleration Motion
It's a type of motion in which the velocity (or the speed) of an object changes by an equal amount in every equal period of time.
Being a the constant acceleration, vo the initial speed, vf the final speed, and t the time, final speed is calculated as follows:
The distance traveled by the object is given by:
(a) The average velocity is defined as the total distance traveled divided by the time taken to travel that distance.
We know the distance is x=640 m and the time taken t= 40 s, thus:
The average velocity is 16 m/s
Using the equation [1] we can solve for a:
(c) From [2] we can solve for a:
Since vo=8 m/s, x=640 m, t=40 s:
The acceleration is 0.4 m/s^2
(b) The final velocity is calculated by [1]:
The final velocity is 24 m/s
The average velocity is 16 m/s, the final velocity is 8.0 m/s + (acceleration * 40 s), and the acceleration can be found by solving the equation 640 m = (8.0 m/s * 40 s) + (0.5 * acceleration * (40 s)^2.
To find the average velocity, we use the formula: average velocity = total displacement / total time. In this case, the total displacement is 640 m and the total time is 40 s, so the average velocity is 640 m / 40 s = 16 m/s.
To find the final velocity, we can use the formula: final velocity = initial velocity + (acceleration * time). In this case, the initial velocity is 8.0 m/s and the time is 40 s. Since the question states that it moves with constant acceleration, we can assume that the acceleration is the same throughout the 40 s interval. Therefore, the final velocity is 8.0 m/s + (acceleration * 40 s).
To find the acceleration, we can use the formula: total displacement = (initial velocity * time) + (0.5 * acceleration * time^2). In this case, the total displacement is 640 m, the initial velocity is 8.0 m/s, and the time is 40 s. Solving for acceleration, we have 640 m = (8.0 m/s * 40 s) + (0.5 * acceleration * (40 s)^2).
#SPJ3
Answer:
All are true except the last point that says that a battery is a current source and the current at the outlet is always the same.
Explanation: